Rotatable chair

ABSTRACT

A rotatable chair comprising a backrest unit, a seat plate unit, a supporting unit and a rotating unit; the rotating unit comprises an upper plate, a lower plate, a rotating disc, a connecting shaft, a first elastic ball and a handle; the backrest unit and the seat plate unit are fixed to the upper plate; the upper plate is provided with an upper locating hole; the supporting unit is fixed to the lower plate; the lower plate is provided with a plurality of lower locating holes; the rotating disc is disposed between the upper plate and the lower plate; the connecting shaft penetrates through the central position of the upper plate, the rotating disc and the lower plate at the same time; the first elastic ball comprises an elastic piece and a locating ball.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a chair, and more particularly, to arotatable chair.

BACKGROUND OF THE INVENTION

In a modern society, the aging population has inevitably become aserious problem. Therefore, nursing people who are old, sick, weak anddisabled is particularly important. A reasonable design of the chair iscrucial for users who need to sit on the chair for a long time. However,traditional wheelchairs sold on the market usually adopt a fixedstructure. This inconvenient arrangement makes it difficult for users totransfer onto a bed or other instruments from the chair.

SUMMARY OF THE INVENTION

The purpose of the present invention is to solve the shortcomings in theprior art and provide a rotatable chair.

To achieve the above purpose, the present invention adopts the followingtechnical solution:

A rotatable chair comprising a backrest unit, a seat plate unit, asupporting unit and a rotating unit; the rotating unit comprises anupper plate, a lower plate, a rotating disc, a connecting shaft, a firstelastic ball and a handle; the backrest unit and the seat plate unit aredisposed above the upper plate, and are fixed to the upper plate; theupper plate is provided with an upper locating hole; the supporting unitis disposed underneath the lower plate, and is fixed to the lower plate;the lower plate is provided with a plurality of lower locating holes;the plurality of lower locating holes is distributed in the front, rear,left and right directions of the lower plate; the rotating disc isdisposed between the upper plate and the lower plate; a plurality ofrolling balls is uniformly distributed on the rotating disc; the rollingballs simultaneously protrude from the upper surface and the lowersurface of the rotating disc; the connecting shaft penetrates throughthe central position of the upper plate, the rotating disc and the lowerplate simultaneously, thereby positioning the upper plate, the rotatingdisc and the lower plate in a radial direction; the first elastic ballcomprises an elastic piece and a locating ball; the elastic piece isdisposed on the upper plate; the locating ball, which is molded with theelastic piece and is located in the upper locating hole, possesses apotential energy of moving towards the lower plate; when the lowerlocating hole and the upper locating hole are butted, the locating ballenters into the lower locating hole; one end of the handle is connectedto the first elastic ball, and the other end of the handle is disposedon the outer side of the upper plate; the handle can be pressed to leverthe locating ball to escape the lower locating hole.

In another preferred embodiment, the rotating unit comprises an upperdisc and a lower disc. The upper disc is disposed between the upperplate and the rotating disc, and the lower disc is disposed between thelower plate and the rotating disc.

In another preferred embodiment, the rotating unit comprises a locatingsquare tube. The locating tube is threaded with the upper surface of theupper plate, and the first elastic ball is disposed in the locatingsquare tube.

In another preferred embodiment, the supporting unit comprises a firstsupporting leg and a second supporting leg that are arranged in acrosswise manner. The first supporting leg and the second supporting legrespectively comprise a chair-leg bending tube and a telescopic leg thatis connected to the chair-leg bending tube. The chair-leg bending tubeis connected to the lower plate.

In another preferred embodiment, the telescopic leg comprises an innertube and an outer tube. The inner tube is provided with a plurality offirst holes. Further, the outer tube is provided with a plurality ofsecond holes that are arranged along the outer tube in an axialdirection. A plurality of second elastic balls are disposed in the innertube. The second elastic balls penetrate through the first hole and thesecond hole that are butted at the same time.

In another preferred embodiment, a leg sleeve is mounted at the lowerend of the outer tube.

In another preferred embodiment, the backrest unit comprises a backrestbending tube, backrest sleeves and a backrest plate. The backrestsleeves are mounted on the upper plate. The backrest bending tube isconnected to the backrest sleeves, and the backrest plate is mounted onthe backrest bending tube.

In another preferred embodiment, the seat plate unit comprises a chairplate, armrest bending tubes and armrest sleeves. The armrest sleevesare mounted on the backrest sleeves. The armrest bending tubes areconnected to the end portion of the armrest sleeves, and the chair plateis mounted on the armrest sleeves.

Compared with the prior art, the present invention has the followingadvantages:

Normally, the locating ball is positioned in the upper locating hole andthe lower locating hole at the same time so that the upper plate and thelower plate can be positioned. When the direction needs to be adjusted,the handle can be pressed down by the user. As a result, the locatingball is levered to escape the lower locating hole through the leverprinciple. The upper plate can rotate relative to the lower plate,thereby changing the orientation of the user sitting on the chair plate.Thus, the movement of the user can be facilitated. After the directionis established, the handle can be loosened and the locating ballre-enters into the lower locating hole, and the upper plate and thelower plate are re-positioned. Thus, the chair is more stable and safe.

BRIEF DESCRIPTION OF THE DRAWINGS

To clearly expound the technical solution of the present invention, thedrawings and embodiments are hereinafter combined to illustrate thepresent invention. Obviously, the drawings are merely some embodimentsof the present invention and those skilled in the art can associatethemselves with other drawings without paying creative labor.

FIG. 1 is an explosive view of the rotatable chair of the presentinvention;

FIG. 2 is a schematic diagram of the seat plate unit of the presentinvention;

FIG. 3 is a schematic diagram of the backrest unit of the presentinvention;

FIG. 4 is schematic diagram of the rotating unit of the presentinvention;

FIG. 5 is a schematic diagram of the supporting unit of the presentinvention;

FIG. 6 is a schematic diagram illustrating the assembled rotatable chairof the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Drawings and detailed embodiments are combined hereinafter to elaboratethe technical principles of the present invention.

As shown in FIGS. 1-6, the rotatable chair comprises a backrest unit 2,a seat plate unit 1, a supporting unit 4 and a rotating unit 3. Therotating unit 3 comprises an upper plate 31, a lower plate 32, arotating disc 35, a connecting shaft 39, a first elastic ball 38 and ahandle 37. The upper plate 31 is square-shaped. The backrest unit 2 andthe seat plate unit 1 are disposed above the upper plate 31, and arefixed to the upper plate 31. The upper plate 31 is provided with anupper locating hole. The lower plate 32 is also square-shaped. Thesupporting unit 4 is disposed underneath the lower plate 32, and isfixed to the lower plate 32. The lower plate 32 is provided with fourlower locating holes, which are distributed in the front, rear, left andright directions of the lower plate 32. When the upper plate 31 rotatesrelative to the lower plate 32, the upper locating hole can be buttedwith any lower locating hole. The rotating disc 35 is disposed betweenthe upper plate 31 and the lower plate 32. A plurality of rolling ballsis uniformly distributed on the rotating disc 35, and the rolling ballssimultaneously protrude from the upper surface and the lower surface ofthe rotating disc 35. Thus, the friction produced between the rotatingdisc 35 and the contact bodies can be effectively reduced due to thisrolling friction. The connecting shaft 39 penetrates through the centralposition of the upper plate 31, the rotating disc 35 and the lower plate32 at the same time, thereby positioning the upper plate 31, therotating disc 35 and the lower plate 32 in a radial direction. The firstelastic ball 38 comprises a U-shaped elastic piece 381 and a cylindricallocating ball 382. The elastic piece 381 is disposed on the upper plate31. The locating ball 382 is molded with one end of the elastic piece381, and is located in the upper locating hole. Under the action of theelastic piece 381, the locating ball 382 possesses a potential energy ofmoving towards the lower plate 32. Namely, when the lower locating holeis butted with the upper locating hole, the locating ball 382 entersinto the lower locating hole. One end of the handle 37 is connected tothe first elastic ball 38, and the other end of the handle 37 isdisposed on the outer side of the upper plate 31. The handle 37 can belevered up and down, through which the locating ball 382 can be leveredto leave the lower locating hole. Through the first elastic ball 38, theupper locating hole and the lower locating hole, the upper plate 31 andthe lower plate 32 can be easily positioned. The rotatable chair of thepresent invention has a simple structure, which is cost-effective andcan be conveniently operated by users.

Furthermore, the rotating unit 3 comprises an upper disc 34 and a lowerdisc 33. The upper disc 34 is disposed between the upper plate 31 andthe rotating disc 35, and the lower disc 33 is disposed between thelower plate 32 and the rotating disc 35. The upper disc 34 and the lowerdisc 33 are respectively provided with a central hole, and are coaxiallyarranged with the upper plate 31. The upper disc 34 is placed betweenthe upper plate 31 and the rotating disc 35, and the lower disc 33 isplaced between the rotating disc 35 and the lower plate 32. Such aconfiguration facilitates the rotation between the upper plate 31 andthe lower plate 32, and increases the structural strength between theupper plate 31 and the lower plate 32.

The rotating unit 3 comprises a locating square tube 36. The locatingsquare tube 36 is threaded with the upper surface of the upper plate 31,and the first elastic ball 38 is disposed in the locating square tube36. Namely, one end of the elastic piece 381 abuts against the upperinner surface of the locating square tube 36, and the other end of theelastic piece 381 corresponds to the upper locating hole. Thus, thelocating ball 382 is located in the upper locating hole, and the elasticpiece 381 is in a compressed state. The elastic piece 381 is connectedto the tube wall of the locating square tube 36 through bolts so thatthe stability of the elastic piece 381 can be further ensured. Thehandle 37 is connected to one end of the locating ball 382 that facestowards the elastic piece 381.

Further, the upper plate 31 includes a handle fulcrum 5, through whichthe handle can be conveniently pressed.

The upper plate 31 is provided with a reset stop block 6. When the seatplate unit 1 returns to the initial position after rotating for acertain angle, the handle 37 abuts against the reset stop block 6. Thus,the upper locating hole can be butted with the lower locating hole,enabling the seat plate unit 1 to be conveniently reset.

The supporting unit 4 comprises a first supporting leg 41 and a secondsupporting leg 42 that are arranged in a crossed manner. The firstsupporting leg 41 and the second supporting leg 42 respectively comprisea chair-leg bending tube 411 and a telescopic leg 412 that is connectedto the chair-leg bending tube 411. The chair-leg bending tube 411 isconnected to the lower plate 32 through bolts. The chair-leg bendingtube 411 is configured to be U-shaped. The telescopic leg 412 comprisesan inner tube 4121 and an outer tube 4122. The inner tube 4121 isprovided with two first holes, which are formed on the side wall of thetwo ends of the inner tube 4121. The outer tube 4122 is provided with aplurality of second holes that are arranged along the outer tube 4122 inan axial direction. Two second elastic balls 4123 are disposed in theinner tube 4121. The two second elastic balls 4123 respectivelycorrespond to the two first holes, and each second elastic ball 4123protrudes from the exterior of the inner tube 4121 through thecorresponding first hole. The upper end of the inner tube 4121 islocated at the exterior of the outer tube 4122, and is engaged with thechair-leg bending tube 411 through the second elastic ball 4123. Thelower end of the inner tube 4121 is located in the outer tube 4122. Whenthe second elastic ball 4123 penetrates through the first hole and thesecond hole that are butted at the same time, the inner tube 4121 andthe out tube 4122 can be connected and positioned. Meanwhile, the innertube 4121 and the outer tube 4122 can coordinate with each other toachieve a telescopic function when the first hole is butted withdifferent second holes. By means of the telescopic leg 412 of thepresent invention, the height of the seat plate unit 1 can beeffectively adjusted. Thus, users with different heights canconveniently use the chair, and perform different operations whensitting on the chair.

A leg sleeve is mounted at the lower end of the outer tube 4122, therebyensuring the stability of the chair.

Additionally, the backrest unit 2 comprises a backrest bending tube 22,a backrest sleeve 23 and a backrest plate 21. There are two backrestsleeves 23. The two backrest sleeves are mounted on the upper plate 31in parallel through bolts. The backrest bending tube 22 is inserted intothe end portion of the backrest sleeve 23, and is engaged with the endportion of the backrest sleeve 23 through the elastic balls. Thebackrest plate 21 is mounted on the backrest bending tube 22 throughbolts. In such a way, the chair can be conveniently disassembled andtransported.

The seat plate unit 1 comprises a chair plate 11, an armrest bendingtube 12 and an armrest sleeve 13. There are two armrest sleeves 13. Thetwo armrest sleeves are mounted on the backrest sleeves through bolts,and are perpendicular to the backrest sleeves 23. There are two armrestbending tubes 12. The two armrest bending tubes are respectivelyinserted into the two ends of the armrest sleeves 13, and are engagedwith the armrest sleeves 13 through the elastic balls. The chair plateis mounted on the armrest sleeves 12 though bolts. Users can leanagainst the armrests. The seat plate unit 1 is a detachable structure,which can be conveniently disassembled and transported.

The description of above embodiments allows those skilled in the art torealize or use the present invention. Without departing from the spiritand essence of the present invention, those skilled in the art cancombine, change or modify correspondingly according to the presentinvention. Therefore, the protective range of the present inventionshould not be limited to the embodiments above but conform to the widestprotective range which is consistent with the principles and innovativecharacteristics of the present invention. Although some special termsare used in the description of the present invention, the scope of theinvention should not necessarily be limited by this description. Thescope of the present invention is defined by the claims.

1. A rotatable chair, comprising: a backrest unit, a seat plate unit, asupporting unit, and a rotating unit, wherein the rotating unitcomprises an upper plate, a lower plate, a rotating disc, a connectingshaft, a first elastic ball and a handle, wherein the backrest unit andthe seat plate unit are disposed above the upper plate, and are fixed tothe upper plate, wherein the upper plate is provided with an upperlocating hole, wherein the supporting unit is disposed underneath thelower plate, and is fixed to the lower plate, wherein the lower plate isprovided with a plurality of lower locating holes, wherein the pluralityof lower locating holes is distributed in the front, rear, left andright directions of the lower plate, wherein the rotating disc isdisposed between the upper plate and the lower plate, wherein aplurality of rolling balls is uniformly distributed on the rotatingdisc, wherein the rolling balls simultaneously protrude from the uppersurface and the lower surface of the rotating disc, wherein theconnecting shaft penetrates through the central position of the upperplate, the rotating disc and the lower plate at the same time, therebypositioning the upper plate, the rotating disc and the lower plate in aradial direction, wherein the first elastic ball comprises an elasticpiece and a locating ball, wherein the elastic piece is disposed on theupper plate, wherein the locating ball, which is molded with the elasticpiece and is located in the upper locating hole, possesses a potentialenergy of moving towards the lower plate, wherein when the lowerlocating hole and the upper locating hole are butted, the locating ballenters into the lower locating hole, wherein one end of the handle isconnected to the first elastic ball, and the other end of the handle isdisposed on the outer side of the upper plate, wherein the handle can bepressed to lever the locating ball to escape the lower locating hole. 2.The rotatable chair of claim 1, wherein the rotating unit comprises anupper disc and a lower disc, wherein the upper disc is disposed betweenthe upper plate and the rotating disc, and the lower disc is disposedbetween the lower plate and the rotating disc.
 3. The rotatable chair ofclaim 2, wherein the rotating unit comprises a locating square tube,wherein the locating tube is threaded with the upper surface of theupper plate, and the first elastic ball is disposed in the locatingsquare tube.
 4. The rotatable chair of claim 1, wherein the supportingunit comprises a first supporting leg and a second supporting leg thatare arranged in a crossed manner, wherein the first supporting leg andthe second supporting leg respectively comprise a chair-leg bending tubeand a telescopic leg that is connected to the chair-leg bending tube,wherein the chair-leg bending tube is connected to the lower plate. 5.The rotatable chair of claim 4, wherein the telescopic leg comprises aninner tube and an outer tube, wherein the inner tube is provided with aplurality of first holes, wherein the outer tube is provided with aplurality of second holes that are arranged along the outer tube in anaxial direction, wherein a plurality of second elastic balls aredisposed in the inner tube, wherein the second elastic balls penetratethrough the first hole and the second hole that are butted at the sametime.
 6. The rotatable chair of claim 5, wherein a leg sleeve is mountedat the lower end of the outer tube.
 7. The rotatable chair of claim 1,wherein the backrest unit comprises a backrest bending tube, backrestsleeves and a backrest plate, wherein the backrest sleeves are mountedon the upper plate, wherein the backrest bending tube is connected tothe backrest sleeves, and the backrest plate is mounted on the backrestbending tube.
 8. The rotatable chair of claim 7, wherein the seat plateunit comprises a chair plate, armrest bending tubes and armrest sleeves,wherein the armrest sleeves are mounted on the backrest sleeves, whereinthe armrest bending tubes are connected to the end portion of thearmrest sleeves, and the chair plate is mounted on the armrest sleeves.